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High Protection with High Safety RRS feed

  • Question

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    So I get that in this mode I don't get automated failover since no witness is required, correct? Can you run high protection with safety switch low (no right?).

     

    For some reason I thought I read in BOL that in this mode, the servers must be able to communicate to fail them over -- so if a server went down, how would I fail that over? In High Availability I guess quorum would be lost and it would happen automatically  - but that didn't seem right to me in this case since I was driving the failover myself Did I get this wrong.

    Friday, August 22, 2008 11:08 AM

Answers

  • The High Protection operating mode also has transactional safety FULL, but has no witness server as part of the mirroring session. The principal database does not need to form a quorum to serve the database. In this mode only a manual failover is possible, because there is no witness to fill the tie-breaker role. An automatic failover is not possible, because if the principal server fails, the mirror server has no witness server with which to form a quorum.

    Since there is no witness server defined, automatic failover cannot occur and a principal server which suddenly loses its quorum with the mirror does not take its database out of service

     

     

    You can cause a forced service on the mirror by invoking the ALTER DATABASE command:

     

    ALTER DATABASE AdventureWorks SET PARTNER FORCE_SERVICE_ALLOW_DATA_LOSS;

     

    Ref-BOL

     

    BR

    Praveen Barath

     

     

    Friday, August 22, 2008 12:48 PM
    Answerer